System and method for controlling an electrical receptacle

ABSTRACT

An electrical receptacle including an outlet for electrically connecting to an external load, a load terminal electrically connected to the outlet, a line terminal electrically connected to a line and configured to receive line power, an interrupting device, and a testing circuit. The interrupting device electrically connects the load terminal to the line terminal when in a first condition and electrically disconnects the load terminal and the line terminal when in a second condition. The testing circuit is configured to determine when the external load is electrically connected to the outlet, and place the interrupting device in the first condition when the external load is electrically connected to the outlet.

RELATED APPLICATIONS

This application claims the benefit to U.S. Provisional PatentApplication No. 62/532,132, filed on Jul. 13, 2017, the entire contentsof which are incorporated herein by reference.

FIELD

Embodiments relate to electrical receptacles.

SUMMARY

Electrical receptacles, such as ground fault circuit interrupters (GFCI)receptacles, are configured to provide electrical power to an externalload via an outlet.

In one embodiment, the application provides an electrical receptacleincluding an outlet for electrically connecting to an external load, aload terminal electrically connected to the outlet, a line terminalelectrically connected to a line and configured to receive line power,an interrupting device, and a testing circuit. The interrupting deviceelectrically connects the load terminal to the line terminal when in afirst condition and electrically disconnects the load terminal and theline terminal when in a second condition. The testing circuit isconfigured to determine the external load is electrically connected tothe outlet, and place the interrupting device in the first conditionwhen the external load is electrically connected to the outlet.

In another embodiment the application provides a method of controllingan electrical receptacle. The method includes outputting, via acontroller, a test signal and receiving, via the controller, a responsesignal. The method further includes analyzing, via the controller, theresponse signal and determining, based on the analysis of the responsesignal, if an acceptable external load is electrically connected to aoutlet. The method further includes controlling an interrupting devicebased on the determination.

Other aspects of the application will become apparent by considerationof the detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an electrical receptacle according tosome embodiments.

FIG. 2 is a partially exposed view of the electrical receptacle of FIG.1 according to some embodiments.

FIG. 3 is a partially exposed view of the electrical receptacle of FIG.1 according to some embodiments.

FIG. 4 is a block diagram of a testing circuit of the electricalreceptacle of FIG. 1 according to some embodiments.

FIG. 5 is a flow chart illustrate an operation of the electricalreceptacle of FIG. 1 according to some embodiments.

DETAILED DESCRIPTION

Before any embodiments of the application are explained in detail, it isto be understood that the application is not limited in its applicationto the details of construction and the arrangement of components setforth in the following description or illustrated in the followingdrawings. The application is capable of other embodiments and of beingpracticed or of being carried out in various ways.

FIG. 1 illustrates a perspective view of a receptacle 10 according toone embodiment of the invention. In some embodiments, the receptacle 10is a ground fault circuit interrupter (GFCI) device. In someembodiments, the receptacle 10 is configured to provide 120 VAC and/or220 VAC. In some embodiments, the receptacle 10 may include a UniversalSerial Bus (USB) outlet or other direct current (DC) outlet.

The receptacle 10 includes a front cover 12 having a duplex outlet face14 with a phase opening 16, a neutral opening 18, and a ground opening20. The face 14 further has opening 22, accommodating a RESET button 24,an adjacent opening 26, accommodating a TEST button 28, and sixrespective circular openings 30-35. In some embodiments, openings 30 and33 accommodate two respective indicators, such as but not limited to,various colored light-emitting diodes (LEDs). In some embodiments,openings 32 and 34 accommodate respective bright LEDs used, for example,as a nightlight. In some embodiments, opening 31 accommodates aphotoconductive photocell used, for example, to control the nightlightLEDs. In some embodiments, opening 35 provides access to a set screw foradjusting a photocell device or a buzzer (e.g., buzzer 605 described inmore detail below) in accordance with this, as well as other,embodiments.

The receptacle 10 further includes a rear cover 36 secured to the frontcover 12 by eight fasteners 38 (four fasteners 38 are shown in FIG. 1 ,while the other four fasteners 38 are obstructed from view). In someembodiments, the fasteners 38 include a barbed post 50 on the frontcover 12 and a corresponding resilient hoop 52 on the rear cover 36,similar to that which is described in detail in U.S. Pat. No. 6,398,594,the entire contents of which are incorporated herein by reference forall that is taught. A ground yoke/bridge assembly 40 includes standardmounting ears 42 protruding from the ends of the receptacle 10.

FIG. 2 illustrates a perspective view of the receptacle 10 with thefront cover 12 removed to expose manifold 126. Manifold 126 providessupport for a printed circuit board 390 and the yoke/bridge assembly 40.According to one embodiment, manifold 126 includes four dovetailinterconnects 130 that mate with corresponding cavities 132 along anupper edge of the rear cover 36. One dovetail-cavity pair is provided oneach of the four sides of manifold 126 and rear cover 36, respectively.

FIG. 3 is a side elevation view of a core assembly 80 according to someembodiments. Core assembly 80 includes a circuit board, such as aprinted-circuit board (PCB), 82 that supports most of the workingcomponents of the receptacle 10, including the control system 200 (FIG.4 ). Line contact arms 94, 96 pass through transformers 425, 430 with aninsulating separator 97 there between. Line contact arms 94, 96 arecantilevered, their respective distal ends carrying phase and neutralline contacts 102, 104. Load contact arms 98, 100 are also cantileveredwith their respective distal ends carrying phase and neutral loadcontacts 101, 103. The resiliency of the cantilevered contact armsbiases the line contacts 102, 104 and load contacts 101, 103 away fromeach other. Load contact arms 98, 100 rest on a movable contact carriage106, made of insulating (preferably thermoplastic) material.

FIG. 4 is a block diagram illustrating a testing circuit, or controlsystem 200. The control system 200 includes a controller 205. Thecontroller 205 is electrically and/or communicatively connected to avariety of modules or components of the receptacle 10. For example, thecontroller 205 is connected to a line terminal 210, a load terminal 215,an interrupting device 220, a rectifier 225, and an input/output (I/O)module 230.

In some embodiments, the controller 205 includes a plurality ofelectrical and electronic components that provide power, operationalcontrol, and protection to the components and modules within thecontroller 205 and/or the receptacle 10. For example, the controller 205includes, among other things, an electronic processor 235 (for example,a microprocessor or another suitable programmable device) and the memory240.

The memory 240 includes, for example, a program storage area and a datastorage area. The program storage area and the data storage area caninclude combinations of different types of memory, such as read-onlymemory (ROM), random access memory (RAM), Various non-transitorycomputer readable media, for example, magnetic, optical, physical, orelectronic memory may be used. The electronic processor 235 iscommunicatively coupled to the memory 240 and executes softwareinstructions that are stored in the memory 240, or stored on anothernon-transitory computer readable medium such as another memory or adisc. The software may include one or more applications, program data,filters, rules, one or more program modules, and other executableinstructions.

The line terminal 210 is configured to receive a line power. The lineterminal 210 is selectively electrically connected, via the interruptingdevice 220, to the load terminal 215. The load terminal 215 isconfigured to output the line power to an external load electricallyconnected to an outlet 245. In some embodiments, the outlet 245 includesthe duplex outlet face 14 with the phase opening 16, the neutral opening18, and the ground opening 20.

The interrupting device 220 is configured to interrupt the flow of linepower from the line terminal 210 to the load terminal 215. In someembodiments, the interrupting device 220 may include components of thecore assembly 80, for example line contact arms 94, 96, transformers425, 430, contacts 102, 104, load contact arms 98, 100, and contacts101, 103. In other embodiments, the interrupting device 220 includes aseparate electrical switch from the line contact arms 94, 96,transformers 425, 430, contacts 102, 104, load contact arms 98, 100, andcontacts 101, 103. In such an embodiment, the separate electrical switchmay be located between the line terminal 210 and the line contact arms94, 96, transformers 425, 430, contacts 102, 104, load contact arms 98,100, and contacts 101, 103. In another embodiment, the separateelectrical switch may be located between the load terminal 215 and theline contact arms 94, 96, transformers 425, 430, contacts 102, 104, loadcontact arms 98, 100, and contacts 101, 103. In yet another embodiment,the separate electrical switch may be located between the load terminal215 and the outlet 245.

Although illustrated as a single line terminal 210, a single loadterminal 215, and single interrupting device 220, in other embodiments,the receptacle 10 may include two or more individually functioning lineterminals 210, load terminals 215, and interrupting devices 225. Forexample, a first line terminal, a first load terminal, and a firstinterrupting device may correspond to a first outlet of the receptacle10, while a second line terminal, a second load terminal, and a secondinterrupting device may correspond to a second outlet of the receptacle10.

The rectifier 225 is configured to rectify the line power to a nominalpower for use by the controller 205. In some embodiments, the rectifier225 rectifies alternating current (AC) power to a nominal direct current(DC) power.

The I/O module 230 is configured to provide communication between thereceptacle 10 and outside devices (for example, other receptacles,electrical devices, external computers, smart phones, tablets, etc.). Insuch an embodiment, the receptacle 10 may communicate with the one ormore outside devices through a network. The network is, for example, awide area network (WAN) (e.g., the Internet, a TCP/IP based network, acellular network, such as, for example, a Global System for MobileCommunications [GSM] network, a General Packet Radio Service [GPRS]network, a Code Division Multiple Access [CDMA] network, anEvolution-Data Optimized [EV-DO] network, an Enhanced Data Rates for GSMEvolution [EDGE] network, a 3GSM network, a 4GSM network, a DigitalEnhanced Cordless Telecommunications [DECT] network, a Digital AMPS[IS-136/TDMA] network, or an Integrated Digital Enhanced Network [iDEN]network, etc.). In other embodiments, the network is, for example, alocal area network (LAN), a neighborhood area network (NAN), a home areanetwork (HAN), or personal area network (PAN) employing any of a varietyof communications protocols, such as Wi-Fi, Bluetooth, ZigBee, etc. Inyet another embodiment, the network includes one or more of a wide areanetwork (WAN), a local area network (LAN), a neighborhood area network(NAN), a home area network (HAN), or personal area network (PAN).

In operation, the testing circuit 200 is normally in a standby mode,wherein the interrupting device 220 electrically disconnects the lineterminal 210 from the load terminal 215. Accordingly, in the standbymode, power is not provided to the outlet 245 and thus, any externalload that may be electrically connected to the outlet 245.

The controller 205 monitors the load terminal 215 to determine if anexternal load is electrically connected to the outlet 245. In someembodiments, the controller 205 monitors the load terminal 215 at apredetermined time period (for example, every 1 μs, every 1 ms, every 1s).

When the controller 205 determines that an acceptable external load iselectrically connected to the outlet 245, the testing circuit 200 isplaced in an operation mode, wherein the interrupting device 220electrically connects the line terminal 210 to the load terminal 215.Accordingly, in the operation mode, power is provided to the outlet 245and thus to the external load electrically connected to the outlet 245.

In the illustrated embodiment, the testing circuit 200 includes afeedback loop 250 configured to monitor the load terminal 215. Thefeedback loop 250 includes an output 255 and an input 260. In operation,the controller 205 outputs a test signal (for example, a low-level DCvoltage signal), via the output 255, to the load terminal 215. Thecontroller 205 then receives a response signal, via the input 260, fromthe load terminal 215. The controller 205 analyzes the response signalto determine if an external load is electrically connected to the outlet245. In some embodiments, the test signal is output to a phase line ofthe outlet 245 while the response signal is received from a neutral lineof the outlet 245.

In some embodiments, an electrical characteristic (for example, avoltage, a current, a resistance, etc.) of the response signal isanalyzed. In some embodiments, the electrical characteristic correspondsto the external load electrically connected to the outlet 245. Forexample, the electrical characteristic may correspond to a resistance ofthe external load.

FIG. 5 is a flowchart illustrating a process, or operation, 300 of thereceptacle 10. Operation 300 may be performed by testing circuit 200and/or controller 205. It should be understood that the order of thesteps disclosed in method 300 could vary. Additional steps may also beadded to the control sequence and not all of the steps may be required.A test signal is output to the load terminal 215 (block 305). A responsesignal is received (block 310). The response signal is analyzed (block315). A determination is made whether an acceptable external load iselectrically connected to the outlet 245 (block 320).

If an acceptable load is electrically connected to the outlet 245, theinterrupting device 220 electrically connects the line terminal 210 tothe load terminal 215, thus supplying line power to the external load(block 325). Operation 300 then cycles back to block 305. If anacceptable load is not electrically connected to the outlet 245, theinterrupting device 220 electrically disconnects the line terminal 210to the load terminal 215 (block 330). Operation 300 then cycles back toblock 305.

In some embodiments, the receptacle may be controlled by the outsidedevice, via the I/O module 230. For example, a user, via the outsidedevice (for example, a smartphone), may electrically connect/disconnectthe line terminal 210 from the load terminal 215, regardless if anacceptable external load is electrically connected to the outlet 245.

Thus, the application provides, among other things, a system and methodfor determining when an acceptable external load is electricallyconnected to a receptacle and providing power to the external loadaccordingly. Various features and advantages of the application are setforth in the following claims.

What is claimed is:
 1. An electrical receptacle comprising: an outlet configured to electrically connect to an external load; a load terminal electrically connected to the outlet; a line terminal electrically connected to a line and configured to receive line power; an interrupting device electrically connecting the load terminal to the line terminal when in a first condition and electrically disconnecting the load terminal and the line terminal when in a second condition; and a testing circuit including a controller and a feedback loop, the feedback loop including an output and an input of the controller, the testing circuit configured to output, via the output of the controller, a signal to a phase line of the outlet, receive, via the input of the controller, a response signal from a neutral line of the outlet, measure, via the controller, a resistance of the response signal, determine, via the controller, when the external load is electrically connected to the outlet based on the resistance of the response signal, and place the interrupting device in the first condition when the external load is electrically connected to the outlet.
 2. The electrical receptacle of claim 1, wherein the signal is a voltage.
 3. The electrical receptacle of claim 2, wherein the voltage is a direct current voltage.
 4. A method of controlling an electrical receptacle including an outlet, a testing circuit having a controller and a feedback loop, the feedback loop including an output and an input of the controller, the method comprising: outputting, via the output of the controller, a test signal to a phase line of the outlet; receiving, via the input of the controller, a response signal from a neutral line of the outlet; measuring, via the controller, a resistance of the response signal; determining, via the controller and based on the resistance of the response signal, if an acceptable external load is electrically connected to an outlet; and controlling an interrupting device based on the determination.
 5. The method of claim 4, wherein the test signal is output to at least one selected from the group consisting of a load terminal and the outlet.
 6. The method of claim 4, wherein the interrupting device is configured to electrically connect the line terminal to the load terminal. 